Khafajah or Khafaje (Arabic: خفاجة), ancient Tutub, is an archaeological site in Diyala Governorate, Iraq 7 miles (11 km) east of Baghdad. Khafajah lies on the Diyala River, a tributary of the Tigris. Occupied from the Uruk and Jemdet Nasr periods through the end of the Old Babylonian Empire, it was under the control of the Akkadian Empire and then the Third Dynasty of Ur in the 3rd millennium BC. It then became part of the empire of the city-state of Eshnunna lying 12 miles (19 km) southwest of that city, about 5 miles (8.0 km) from the ancient city of Shaduppum, and near Tell Ishchali, both of which Eshnunna also controlled. It then fell to First Babylonian Empire before falling into disuse. The city of Tutub is mentioned in a fragmentary Sumerian temple hymn "... To the shrine Nippur, to the Duranki <we go>, To ..., to the brickwork of Tutub <we go>, To the lofty Abzu ...".

The site of Tulul Khattab (also Telul Khattab) lies 13 kilometers away and at over 50 hectares is one of the largest in the area. The site consists of 14 sub-mounds and it was excavated in 1979 (as it was being exploited by brickmaking industries) recovering 379 Old Babylonian period cuneiform tablets and fragments (225 on Mound 1 and 154 on Mound 2), which featured nine year names of Eshnunna rulers including "Year 2 of Ṣillī-Sîn as king". Only a handful of the tablets have been published.

Khafajah was excavated for 7 seasons between 1930 and 1937 by an Oriental Institute of Chicago team led by Henri Frankfort with Thorkild Jacobsen, Conrad Preusser and Pinhas Delougaz. Before the work began looters had dug a large number of deep pits at various points in the site. Many artifacts from these illicit digs ended up in various museums and private collections in the decades preceding the start of excavations. For two seasons, in 1937 and 1938, the site was worked by a joint team of the American Schools of Oriental Research and the University of Pennsylvania led by Delougaz. They worked primarily in the Nintu temple on mound A (along with the cemetery to the east and northeast of the temple) and with soundings on mound B. Among the small finds at the site was an Akkadian period die. and a terracotta incantation bowl written in "typical Jewish Babylonian Aramaic of the Sasanian period".

The site consists of four mounds, labeled A through D.

The main one, Mound A which lies 4 meters above the plain, extends back as far as the Uruk period and contained a large oval temple, a temple of the god Sin, and a small temple of Nintu (where a bearded cow statue was found), dating back to the Jemdet Nasr and Early Dynastic periods. An early radiocarbon date for the first level of the Sin Temple returned a corrected date of 4963 BC which is thought to be somewhat too early and possibly contaminated. The mound was occupied through the Akkadian Empire period and then abandoned. Its name, Tutub, is not known before the Akkadian times. A number of vaulted tombs made out of plano-convex bricks were found. About 70 Akkadian Period cuneiform tablets were found there. Most of the tablets were administrative in nature and were apportioned half to the Oriental Institute and half to the Baghdad Museum. A defensive wall surrounding Mound A was encountered in a number of places with a width of 6 to 8 meters and unknown full extent. It was not fully excavated so the dating is uncertain.

A large number of private houses were excavated on Mound A, almost all from the Early Dynastic period. At the lowest point above the water table were some homes of the "Protoliterate period". Finds there included a numerical tablet (Kh. V 338) dated to the Uruk V period c. 3500 BC. Other small finds from that level included stone stamp seals, clay figurines, a stone macehead, and four cylinder seals. At the top level foundations of Akkadian Empire period residences were excavated. An enormous number of small finds emerged from the Early Dynastic period homes including many cylinder seals, faience and lapis lazuli beads, metal tools and other metal objects, spindle whorls, stone weights, figurines, pendants, amulets, clay model chariot wheels, and a number of cuneiform tablets. A number of Early Dynastic burials, 168 in total and mostly intramural (inside homes) with a few having multiple skeletons, were excavated. Burials were mostly inhumations with simple grave goods, mainly pottery but with the occasional cylinder seal, copper tool, etc. There were also 4 Plano-convex brick tombs and 24 Plano-convex brick vaulted tombs some holding much more extensive grave goods. A notable residence find (Kh. IX 87) was a hoard of hacksilver found sealed in a jar in the courtyard of a home dated to the Early Dynastic IIIa period. It contained 14 silver spiral rings, 15 silver beads, 2 silver cones, silver ring and 14 fragments of silver rings and wire, 13 fragments of silver foil, a silver ingot, 9 silver strips and 30 pieces of melted-down silver and scraps. The items were divided between the Baghdad Museum and the Penn Museum.

Five religious structures were found on Mound A, the Temple Oval, and located to the east of the Temple Oval and north of the summit of the Mound, Large Temple ("Sin Temple"), Small Temple, Nintu Temple, and Small Single Shrine, all within a 100 square meter area:

Temple Oval - The Temple Oval had three building phases, all in the Early Dynastic period. A few partial Akkadian Empire period inscriptions were found indicating it remained in use at least for a time in that period. The Temple Oval bears may similarities to the contemporary temple of Ninḫursaĝ at Tell al-'Ubaid.